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Care of living organismsThis page should describe the care of living organisms in a school science laboratory, other than humans.
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The most common plant to be found in a school science lab is the geranium Pelargonium[?]. They are very easy to grow and tolerate abuse well. They can be propagated from cuttings very easily. Take a section of geranium with one or two smallish leaves and leave in water for 2 to 3 weeks. When you see the roots growing pot into sandy compost. Cuttings should be taken on a regular basis to replace old plants, which tend to become woody and unattractive after a couple of years laboratory abuse.
Geraniums are good for the following experiments:
Water snails [ Limnaea[?] and others] can be purchased in the UK from Blades Biological. You can easily obtain snails from garden ponds and clean canals, or from many pet shops which stock fish. They help to keep a cold water fish tank clean and free of algae. They can be used to investigate respiration and the carbon cycle see using water snails and pond weed to investigate the carbon cycle
Stick insects[?] come in a variety of species and by and large are very easy to keep. Beware some species of stick insect reproduce asexually and you will be overrun with little stick insects unless you remove the eggs. They typically live for about 18 months, and [depending on the species] feed on brambles or privet.
Start your own breeding tank: The best way to get woodlice at all times of the year (and no need to go searching under stones if ordered at the last minute). Use a large opaque plastic box with a lid; about 3-5cms of fine soil in the bottom; A couple of lumps of chalk; Some clumps of damp cotton wool; A source of food, eg celery, potato, leaves. According to which type and age range of woodlice you start with they should start breeding within a few weeks/months (some even upto 2 years to reach breeding age). If planning to be used for detailed investigation, only put one species in the tank, unless you want a selection of offspring.
Culture Daphnia (Water flea) in an aerated aquarium filled with tap water. Allow the water to stand for 24 hours to equilibrate dissolved gasses.
Make a suspension of yeast in water, and pipette enough into the aquarium to just give the water a milky tinge. Introduce the Daphnia. When they clear the yeast from the tank, add a similar amount. If the tank is left in daylight, algae can grow on the sunlit side. This can be scraped off and broken up, and adds to the diet of yeast. Change the water completely once a month.
One interesting, if slightly morbid way of cleaning 'green' tropical fish tanks of algae is to remove the fish into a second tank, and add Daphnia to the algal soup. After a couple of weeks, when the Daphnia have eaten the algae, re-introduce the fish. This is also an excellent demonstration of a food chain in action.
Run yer hand.html">hand int' my throat an I'll let ye hev it."
'The bear.html">bear.html">bear he opened his mouth.html">mouth.html">mouth an' showed his big.html">big teeth.'
'Whew!' I whistled.
'Thet's eggszac'ly what he done,' said Uncle Eb. 'He showed 'em
down on his hind legs 'n laughed 'n' hollered 'n' shook himself
'"Only jes' foolin," says he, when he see.html">see the boy.html">boy.html">boy.html">boy.html">boy.html">boy was goin' t' run
shet."
'An the bear he shet his mouth 'n pinted to the big pocket 'n his fur
The boy slid his hand in up t' the elbow. Wha' d'ye s'pose he
and gave up.
'Gingerbread,' said he, soberly, at lengrh.
'Thought ye said bears couldn't talk" I objected.
'Wall, the boy 'd fell asleep an' he'd only dreamed o' the bear,' said
Come daylight, the boy got up 'n ketched a crow.html">crow.html">crow.html">crow. Broke his wing.html">wing
an' the crow flopped along 'n the boy followed him 'n bime bye
his dinner.'
'What 'come o' the boy?' said I.
'Went home,' said he, gaping, as he lay on his back and looked up
only keep his mouth shet - jes' like some folks I've hearn uv.'
'An' what 'come o' the crow?'
'Went t' the ol' crow doctor 'n got his wing fixed,' he said, drowsily.
I could just see Uncle Eb in the dim light.html">light of the fire, kneeling
although Fred was growling ominously, his hair on end. As for
before the light of morning came.
I made no outcry, but clung to my old companion, trembling. He
small hemlocks on one side of the opening.
'Keep still,' he whispered, 'don't move er speak.'
Presently we heard a move in the brush and then quick as a flash
loud echo had gone off in the woods we heard something.
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